Received 6 July 2008; accepted 29 October 2008; published online 31 October 2008

Abstract - Porcine circovirus type 2 (PCV2) is an economically important pathogen. It has been
demonstrated that PCV2 DNA can be detected in boar semen by PCR; however, the biological
relevance of this is unknown. The objectives of this study were to determine if semen positive
for PCV2 DNA is infectious (1) in a swine bioassay, or (2) when used for artificial insemination.
For the first objective, 4-week-old pigs were inoculated intraperitoneally with PCV2 DNA-negative
(bioassay-control; n = 3), PCV2a DNA-positive (bioassay-PCV2a; n = 3), or PCV2b DNA-positive
(bioassay-PCV2b; n = 3) raw semen, or PCV2 live virus (bioassay-positive; n = 3), respectively. Pigs inoculated with PCV2 DNA-positive semen and PCV2 live virus became viremic and developed
anti-PCV2 antibodies indicating that the PCV2 DNA present in semen was infectious. For the second
objective, three Landrace gilts were inseminated with PCV2 DNA-negative semen (gilts-controls) from
experimentally-infected boars, and six gilts were artificially inseminated with semen positive for PCV2a DNA (gilts-PCV2a; n = 3) or PCV2b DNA (gilts-PCV2b; n = 3). Serum samples collected from the gilts in all groups remained negative for anti-PCV2 antibodies for the duration of the experiment. In addition, fetal serum samples from all 105-day-gestation fetuses were negative for anti-PCV2 antibodies or PCV2 DNA. Under the conditions of this study, PCV2 DNA-positive semen was not infectious when used to artificially inseminate gilts; however, it was demonstrated to be infectious in a swine bioassay model and therefore is a potential means of PCV2 transmission amongst swine herds.